Self-knowledge or Bramha Gnana or Atma Gnana is knowledge of undifferentiated Reality.

Self-knowledge or Bramha Gnana or Atma Gnana   is knowledge of undifferentiated Reality.  Self-knowledge or Bramha Gnana or Atma Gnana is difficult to understand even with the help of the gurus or various Scriptures or gurus because it is the knowledge of the innermost self. The seeker has to ascertain and realizes on his own.

Self-awareness means becoming aware of with formless non-dual Consciousness, which is the innermost Self. Self-knowledge clears all the cobwebs of doubts and confusion and frees one from   absolutely from all concepts.

When one scrutinizes mind, which is in the form of the universe he realizes that, it does not really exist and the mind or the universe is a mere mirage created out the undifferentiated consciousness, which is the innermost self. 

When the Self-knowledge or Bramha Gnana or Atma Gnana becomes firm with the conviction by clinging to the truth, one is able discard the untruth mentally than the ignorance vanishes and the mind becomes one with the source, from where it used to rise and subside as waking or dream. The consciousness is the formless substance, witness and the source of the mind or the universe. Thus the formless substance, witness and the source are one in essence and that essence is consciousness.  Thus consciousness is Absolute Reality or Brahman.  

In self-awareness the mind abides as consciousness then there is no duality which is in the form of the mind or the universe. When the mind or the universe is absorbed in consciousness, and then is no trace of reality in the experience of the duality or waking experience.

 In the midst of waking one becomes aware of the fact that his body is not the body his ego is not ego his world is not the world but they too are consciousness. Therefore there is no scope for second thing other than consciousness. –FORMLESS PATH